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Microsoft quietly rewrites its activation rules for Windows 10 - Windows 10 Forums
Which ISO did you download?
The Microsoft Techbench ISO works flawlessly.
There should be text in the lower left of the screen that says
- or -
Do this later
But you really should not be getting that screen.
Maybe you're not doing an upgrade ?!?!
Ztruker said: Right click on the ISO and select Mount.
Run setup.exe from the mounted image to start the upgrade.
So you must be running Windows
you can mount the ISO and it will appear in This PC
or if you have already put it to media (disc or flash drive) - insert the media
Navigate to the drive (mounted or inserted)
launch setup on the drive